*{
    padding: 0;
    margin: 0;
}
body{
    background: #262626;
}
.out{
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%,-50%);
    width: 400px;
    height: 300px;
}
.in{
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
}
.grey{
    filter: grayscale(100%);
    transition: 1s;
}

.in img{
    width: 100%;
    height: 100%;
}
.out:hover .grey{
    filter: grayscale(0%);

}

